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> > Unfortunately, packet drops are the normal method of throttling data > > flow. > > If packets don't get dropped, TCP assumes it's not sending fast enough > > and > > sends faster, limited only by the rate that the sender can produce data > > and the rate the receiver can consume it. > > That's interesting. I'm trying to reconcile that with the behavior I saw > when I used to run a stock FreeBSD 4.x distro on my old P90 as a > firewall. I could ping all day and never have a dropped packet. Same > thing at my parents' house with their Netgear WGT624. > The above explanation from Fred isn't exactly correct. TCP *will* pass data as fast as the sender can produce and the receiver can receive. Dropped packets are by no means a method of throttling, and shouldn't happen frequently if your connection is solid, which it sounds like it is. I run a half dozen netmon graphs on my second screen constantly, behind a m0n0wall box (netmon pings a given host and displays a graph in real time http://www.nullsoft.com/free/netmon/). Therefore, I see all dropped packets. It drops about 1-2% of pings, which I've found is pretty typical for most any internet connection. It's almost certainly not m0n0wall that's dropping those either, it's something else along the way. Keep in mind ICMP is not a reliable protocol, so 1-2% loss on ICMP over several internet hops is good, and would likely equate to 99.9+ % success on TCP packets. A cause might be a machine behind the firewall with a virus that's trying to flood traffic to the internet. That could overload m0n0wall, and/or your internet connection, which would cause dropped packets. Losing 10% of your packets is not normal, and as a rough estimate, would cause you to be wasting maybe as much as half of your bandwidth due to retransmittals. (% packet loss is a fraction of the % wasted bandwidth - 30-40% packet loss makes for a completely unusable connection). -Chris This electronic transmission is intended for the addressee or entity indicated above. It may contain information that is privileged, confidential, or otherwise protected from disclosure. Any review, dissemination or use of this transmission or its contents by persons other than the addressee is prohibited. If you have received this transmission in error, we respectfully request that you notify us immediately and erase all copies of this transmission. Thank You. |